The information that you seek on the installation of AC is on my website.    https://hudsonrestoration1948-54.com/    
On the front page as shown in the attached screen shot of the page is a link called ... adding air condtitioning.   You will find information that will guide you to a solution that has been used by other Stepdown owners ( including me - 1953 Wasp).

Jim ---Are you referring to installing AC in Walt Mordenti's '53 Hudson Hornet? No pun intended but that's COOL! I had the pleasure of meeting Walt and seeing him drive up in that wonderful automobile, with his lovely wife, at a few Club meets in San Simeon, CA. What a wonderful family and car!

I installed a Vintage Air Gen IV Magnum A/C system in a '53 Hornet (4 door) that fits perfectly under the passenger's side dash other than the glovebox had to be sacrificed. Although the engine and drive train in this particular car isn't Hudson, the mounting and plumbing details for evaporator and condenser would be nearly identical. Maybe someone else could provide the compressor installation details.  

Let me know if you'd be interested in seeing some pics. Better yet I'll be sporting the car to this year's San Simeon meet on Saturday, October 1st if you're interested in seeing the install.

[quote="Robert Waid post=30037 userid=12727"]Jim ---Are you referring to installing AC in Walt Mordenti's '53 Hudson Hornet? No pun intended but that's COOL! I had the pleasure of meeting Walt and seeing him drive up in that wonderful automobile, with his lovely wife, at a few Club meets in San Simeon, CA. What a wonderful family and car!

I installed a Vintage Air Gen IV Magnum A/C system in a '53 Hornet (4 door) that fits perfectly under the passenger's side dash other than the glovebox had to be sacrificed. Although the engine and drive train in this particular car isn't Hudson, the mounting and plumbing details for evaporator and condenser would be nearly identical. Maybe someone else could provide the compressor installation details.  

Let me know if you'd be interested in seeing some pics. Better yet I'll be sporting the car to this year's San Simeon meet on Saturday, October 1st if you're interested in seeing the install.

Robert, I will be there too… let’s talk.
 

Dany ---Excellent! I'll buzz you this weekend.

Thank you Robert & Kenneth.  I have printed Kenneth's posts and look forward to seeing Robert in San Simeon.  I don't have time to get it installed before the October meet, but would appreciate pics from Robert.

Jim